Apparatus for abrading and refining foundry

ABSTRACT

An apparatus for abrading and refining foundry sands comprising a sealed vessel which is made from flexible material and means for pressing the vessel successively and continuously.

United States Patent 1191 Takechi et al.

APPARATUS FOR ABRADING AND REFINING FOUNDRY Inventors: Kaoru Takechi, Osaka; Shoji Yamada; Chiaki lshiguro, both of lnuyanashi, all of Japan Murata Kikai Kabushiki Kaisha, Kyotoshi, Japan Filed: Aug. 9, 1972 Appl. No.: 279,180

Assignee:

US. Cl 241/102, 241/284, 241/D1G. 10, 259/72 Int. Cl. B02c 17/04 Field of Search 241/102, 284, 176, DIG. 10, 241/220; 259/72 References Cited UNITED STATES PATENTS 7/1940 Matthews 241/176 X Primary Examiner-Granville Y. Custer, Jr. Assistant Examiner-Howard N. Goldberg Attorney, Agent, or FirmWh1ttemore, Hulbert &

Belknap 5 7 ABSTRACT An apparatus for abrading and refining foundry sands comprising a sealed vessel which is made from flexible material and means for pressing the vessel successively and continuously.

10 Claims, 5 Drawing Figures O 8 I o APPARATUS FOR ABRADING AND REFINING FOUNDRY BACKGROUND OF THE INVENTION A conventional method for refining and reusing foundry sands which have been put to use is to press the sands by a roll to remove adherent impurities that is hardening agent etc. attached to the surfaces of the sands or laying between the sands. This method, however, is not efficient because the rubbing force between the sands is extreamly small in spite of large force added from the roll.

In another conventional method for refining foundary sands, a sand thrower is applied. However it is difficult to remove the adherent impurities from the sands by throwing them in only one direction, and many sands are crushed by throwing requiring that some new sands must be intermixed with the refined sands.

SUMMARY OF THE INVENTION This invention relates to an apparatusfor refining and abrading foundry sands.

An object of the invention is to propose a highly efficient apparatus for refining used sands.

Another object of the invention is to produce foundry sands not including adherent impurities therein.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings show the apparatus in accordance with the present invention, in which:

FIG. 1 is a cross section view of structure illustrating the theory of the invention. I

FIG. 2 is alongitudinal section view of another embodiment of the invention.

FIG. 3 is a cross section view of the structure shown in FIG. 2 taken substantially on line IIIIII in FIG. 2.

FIG. 4 is a longitudinal section view of a further embodiment of the invention.

FIG. 5 is a cross section view of the structure shown in FIG. 4 taken substantially on line V-V in FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION Referring now to FIG. I of the drawing, there is shown the theory of the invention in treatment of old foundry sands which have been put to use. A cylindrical vessel 1 made from flexible material such as rubber contains the old foundry sands 2. The vessel 1 is held between boards 3 and 4 and pressed by them and the one end of the board 3 is joined to a link 5 of a crank chain C. The vessel 1 begins a return motion maintaining its elliptic section when the crank chain C is set in motion adding a pressing force F from the side of the board 3 toward the flexible vessel. Then, successively the surfaces of the vessel 1 are pressed one after another so that the sands put, full and sealed in the vessel rub each other and adherent impurities attached to the surfaces of the sands exfoliate. Thus, foundry sands are abrased and refined. The refined sands may be separate from the exfoliated impurities using a known sizer or rotary classifier. The refined sands with the adherent impurities removed are as clear as newfoundry sands. Referring to FIG. 2 of the drawing, the flexible vessel 1 supported by screwing its upper end and lower end against supporting members 6 and 7 is toothed at its surface. Three cylindrical toothed wheels 8 which are rotatably secured to a supporting member 9 fixed to a base of the apparatus are in gear with the toothed surface of the vessel 1. The flexible vessel 1, put between the cylindrical toothed wheels is held in a triangular shape. As the supporting member 6 is set on the supporting member 9 by a roller member 10, the flexible vessel l is rotatable with respect to the base. A roller member 11 is positioned on the supporting member 9 opposite to each cylindrical toothed wheel 8 and the roller member 11 maintain a shaft line for the flexible vessel 1 contacting with the outside surface of the supporting members 6 and 7. A hopper l2 and an outlet pipe 13 are also secured to the base. The outlet pipe 13 is equipped with a valve 14 to change its sectional area and to adjust the discharging volume of sands. A driving motor 15 transmits rotation to the one cylindrical toothed wheel 8 by a sprocket 16, a chain 17, a sprocket l8 and a shaft 19. If any one of the toothed wheels 8 is rotated as a driving force, the vessel 1 moves and rotates maintaining its triangular cross section shape. Then the sands in the vessel 1 are rubbed against each other and the adherent impurities attached to the surfaces of the sands exfoliate the same with the structure shown in FIG. 1. Thus old used foundry sands may be refined continuously and the vol ume of refined sands discharged may be adjusted by controlling the valve 14 of the outlet pipe 13 in degree of opening and shutting.

FIG. 4 illustrates the third embodiment of the invention, in which the flexible vessel 1 is stationary and is pressed by cylindrical rotating rollls which hold the vessel in its triangular cross section shape and abrase and refine the foundry sands. In FIG. 4, the flexible vessel 1 of which upper end and lower end are screwed to a supporting member 20 is fixed on the base of the apparatus. The vessel 1 is held in triangular shape as shown in FIG. 5 by being put between three cylindrical rolls 21. The cylindrical rolls 21 are rotatably set on the shafts 22. The shafts 22 are fixed by adjusting screws 23 on a rotating member 24 which is supported rotatably by rollers 25 on the base of the apparatus. A roller member 26 is positioned on the rotating member 24 opposite to each cylindrical roll 21. The roller mem bers 26 maintain and fix the shaft line of the rotating member 24 since they contact with the outside surface of the supporting member 20. A sprocket 27 is secured on the outside of the circumferential rotating member 24. A chain 28 is connecting the sprocket 27 to a sprocket 29 which is set on a shaft 30 rotatably supported by the base of the apparatus. A driving motor 31 rotates the rotating member 24 by a pulley 32, a belt 33, a pulley 34 and the shaft 30. A hopper 35 and an outlet pipe 36 connected to the vessel 1 are fixed to the base. When the rotating member 24 is rotated by the driving motor 31, each cylindrical roll 21 is put in motion holding and pressing the vessel 1 and old sands are abrased and refined as described in consideration of the second embodiment shown in FIG. 2.

In this invention, as the sands to be refined powerfully abrase each other, adherent impurities attached to the surfaces of old sands quickly exfoliate and efficiency of refining the old sands becomes extreamly large. Also the invention has the effect that dusts do not scatter out of the apparatus as the sands are treated in a sealed vessel.

In the last two above embodiments, the flexible vessel is held in the triangular shape. However it may be held 1. Apparatus for abrading and refining foundry sands and the like comprising a flexible vessel having an upper and lower opening therein through which material to be abrading and refined may be passed and means engaging the outer surface of the flexible vessel having a surface movable tangentially relative to the surface of the flexible vessel for applying pressure to the flexible vessel and varying the cross section shape of the flexible vessel as the material is passed through the flexible vessel.

2. Structure as set forth in claim 1 wherein the means for deforming the flexible vessel comprises a pair of substantially flat parallel members between which the flexible vessel is positioned, means for applying a force between the parallel members tending to force the parallel members toward each other, and means for oscillating the parallel members relative to each other in a forward and backward direction parallel to the extent of the parallel members.

3. Structure as set forth in claim 2 wherein the means for oscillating the parallel members comprises a rotatable disc and a connecting link pivotally secured to the rotatable disc off-center thereof at one end and to one of the parallel members at the other end thereof extending substantially in the plane of the disc.

4. Structure as set forth in claim 1 wherein the means for changing the shape of the flexible vessel comprises rollers positioned in contact with the flexible vessel axially thereof, means for rotatably supporting the rollers, and means for rotating the rotatably supported rollers in contact with the flexible vessel.

5. Structure as set forth in claim 4 and further including means for rotatably supporting the flexible vessel about an axis of generation thereof.

6. Structure as set forth in claim 5 wherein the flexible vessel is provided with gear teeth centrally thereof and the rollers are similarly provided with gear teeth in mesh with the gear teeth on the flexible vessel whereby the flexible vessel is positively driven by the rollers on rotation of the rollers.

7. Structure as set forth in claim 1 wherein the means for deforming the flexible vessel comprises a rotatable structure positioned around the flexible vessel and supported for rotation about the axis of generation of the flexible vessel, a plurality of rollers extending parallel to the axis of generation of the flexible vessel and in contact therewith supported for rotation by the rotatable structure and relative thereto, and means for positively rotating the rotatable structure.

8. An apparatus for abrasing and refining foundry sands comprising a cylindrical vessel adapted to receive old foundry sands which vessel is opened at the top and at the bottom and has a flexible part, and plural cylindrical toothed wheels in contact with said flexible part of the vesselfor pressing the surface of said flexible part of the vessel successively, said flexible part of the vessel being toothed in a longitudinal direction on its outer surface and said toothed surface of the vessel being engaged with the toothed wheels.

9. An apparatus for abrading andrefining foundry sands comprising a rotating member, a vertically extending cylindrical vessel arranged at the center of said rotating member and adapted to receive old foundry sands which vessel is opened at the top and at the bottom and has a flexible part, and plural rolls supported rotatably and movably around the vessel by the rotating member and engaged with the flexible part of the vessel.

10. Apparatus for abrading and refining foundry sands comprising a vessel adapted to receive old foundry sands or the like which vessel has a flexible part adapted to be changeable in cross section shape, and pressing means to press the surface of said flexible part of the vessel successively including two substantially flat members arranged in opposite positions holding the flexible part of the vessel between them, and means for moving the two substantially flat members in the plane of the members relative to each other in opposite directions in a forward and return motion.

* =l= l =l 

1. Apparatus for abrading and refining foundry sands and the like comprising a flexible vessel having an upper and lower opening therein through which material to be abrading and refined may be passed and means engaging the outer surface of the flexible vessel having a surface movable tangentially relative to the surface of the flexible vessel for applying pressure to the flexible vessel and varying the cross section shape of the flexible vessel as the material is passed through the flexible vessel.
 2. Structure as set forth in claim 1 wherein the means for deforming the flexible vessel comprises a pair of substantially flat parallel members between which the flexible vessel is positioned, means for applying a force between the parallel members tending to force the parallel members toward each other, and means for oscillating the parallel members relative to each other in a forward and backward direction parallel to the extent of the parallel members.
 3. Structure as set forth in claim 2 wherein the means for oscillating the parallel members comprises a rotatable disc and a connecting link pivotally secured to the rotatable disc off-center thereof at one end and to one of the parallel members at the other end thereof extending substantially in the plane of the disc.
 4. Structure as set forth in claim 1 wherein the means for changing the shape of the flexible vessel comprises rollers positioned in contact with the flexible vessel axially thereof, means for rotatably supporting the rollers, and means for rotating the rotatably supported rollers in contact with the flexible vessel.
 5. Structure as set forth in claim 4 and further including means for rotatably supporting the flexible vessel about an axis of generation thereof.
 6. Structure as set forth in claim 5 wherein the flexible vessel is provided with gear teeth centrally thereof and the rollers are similarly provided with gear teeth in mesh with the gear teeth on the flexible vessel whereby the flexible vessel is positively driven by the rollers on rotation of the rollers.
 7. Structure as set forth in claim 1 wherein the means for deforming the flexible vessel comprises a rotatable structure positioned around the flexible vessel and supported for rotation about the axis of generation of the flexible vessel, a plurality of rollers extending parallel to the axis of generation of the flexible vessel and in contact therewith supported for rotation by the rotatable structure and relative thereto, and means for positively rotating the rotatable structure.
 8. An apparatus for abrasing and refining foundry sands comprising a cylindrical vessel adapted to receive old foundry sands which vessel is opened at the top and at the bottom and has a flexible part, and plural cylindrical toothed wheels in contact with said flexible part of the vessel for pressing the surface of said flexible part of the vessel successively, said flexible part of the vessel being toothed in a longitudinal direction on its outer surface and said toothed surface of the vessel being engaged with the toothed wheels.
 9. An apparatus for abrading and refining foundry sands comprising a rotating member, a vertically extending cylindrical vessel arranged at the center of said rotating member and adapted to receive old foundry sands which vessel is opened at the top and at the bottom and has a flexible part, and plural rolls supported rotatably and movably around the vessel by the rotating member and engaged with the flexible part of the vessel.
 10. Apparatus for abrading and refining foundry sands comprising a vessel adapted to receive old foundry sands or the like which vessel has a flexible part adapted to be changeable in cross section shape, and pressing means to press the surface of said flexible part of the vessel successively including two substantially flat members arranged in oppositE positions holding the flexible part of the vessel between them, and means for moving the two substantially flat members in the plane of the members relative to each other in opposite directions in a forward and return motion. 